Abstract
Gastrointestinal endoscopy has completely entered the age of videoscope, as new types of videoscope are developed and improved one after another, providing new functions that prior endoscopes do not have such as various types of image analyses, image processing, data communication, data filing and so on. Obviously, videoscope could not have been brought into practical use without development of broadcasting television technology. The author have briefly explained the history of development of broadcasting television at the beginning. Application of television to endoscopy started with an attempt to project an endoscopic image on a TV monitor by attaching the TV camera tubes on the eyepiece of a f iberscope . It was not until solid-state image sensing device (charge coupled device, CCD) was developed and miniaturized that it became possible to insert a TV camera directly into stomach . The first videoscope was developed and reported in the United States in 1983, and several Japanese manufacturers set out development of videoscope. Today, there are a number of different videoscopes sold in the market. Basing on the explanation of the basic principle and theory of videoscope, development of image processing and analysis functions are illustrated that are gathering attention above all. Moreover, clinical application of infrared ray videoscope and the theory and significance of Narrow Band Imaging (NBI) and AIF (auto-fluorescence Imaging) are also stated as the focus of discussion these days. In relation to these topics, fear for inappropriate stretch of interpretation of the term "special light" is also pointed out with a proposal of a new classification by purposes of endoscopic observation (Niwa, Tajiri). IDTV, EDTV (clear hi-vision) and hi-vision are also introduced as well as liquid crystal display and rear-projection television that can replace CRT display.
